Unit 9 Refrigerant and Oil Chemistry and Management Review Questions

Life wheel assessment

Catarina Farinha , ... Maria Practise Veiga , in Eco-Efficient Rendering Mortars, 2021

8.five.3 Ozone depletion potential

ODP is the EI that represents the reduction of the ozone layer in the temper. This layer is reduced with the concentration of halocarbons in the atmosphere [v] as these gases dissociate the ozone molecules presented, reducing this layer [245]. The depletion of the stratospheric ozone layer increases the radiation that tin accomplish the Earth'south surface, such equally the ultraviolet radiation [232] [245], which results in several climate changes that can affect the ecosystems and human health [five] [232]. ODP is evaluated by a kilogram of CFC-11 (Trichlorofluoromethane) equivalent.

In ODP bear on, sand is the raw material that contributes the most to this impact. It is responsible for 55% of the full impact of the reference mortar, considered every bit a reference in Fig. 8.vii. The mortars' production procedure is the component that comes after sands' impact and information technology is responsible for xl% of the ODP impact. The remaining 5% are distributed by transportation and cement.

Fig. 8.7. Ozone depletion potential—contribution of raw materials, transportation, and mortars production [v] [218].

In Fig. 8.8, the ODP impacts of 9 mortars that straight replaced sand by wastes are illustrated, namely: ruddy ceramics, sanitary ware, CDW (mainly concrete) or CDW, all as aggregates or powders, and GFRP as pulverisation waste. In all, the ODP impact was reduced. The chief reductions tin be noticed in the mortars with germ-free ware and CDW (mainly concrete) that replaced sand at 100%. These mortars decreased the ODP touch on by 59% and 53%, respectively. A binder waste (wood biomass ashes) and the corresponding impact on ODP are also illustrated in Fig. 8.8. It also reduced the impact by 1%, which is non considerable as it did non significantly change the mortars' production or replaced sand. The incorporation of material fibers as an addition of five% likewise resulted in a subtract of the ODP affect by v%.

Fig. 8.8. Ozone depletion potential (in kg CFC-11 - eq.) [5] [49] [154] [155] [218] [221].

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Energy Materials

Ibrahim Dincer , in Comprehensive Energy Systems, 2018

2.15.half-dozen.8 Ozone Depletion Potential

The ODP is a number which refers to the amount of stratospheric ozone depletion caused by a substance. In this regard, ODP was treated as the ratio of the affect on ozone of a chemical compared to the touch on of a similar mass of R-xi. Thus, the ODP of R-eleven was defined to be 1.0. Other CFCs and HCFCs have ODPs which range from 0.01 to i.0. The halons take even college ODPs ranging up to x. The CCl_four has an ODP of i.ii, and the CH₃CCl₃׳south ODP is 0.11. Note that HFCs have zero ODP because they practice not comprise chlorine. The ODP data of all ozone-depleting substances are tabulated in Table 2.

Table 2. ODPs, GWPs, and CAS numbers of Class I and Two ODSs

Chemical name	ODP	GWP	CAS number
Form I
Grouping I
CFC-11 Trichlorofluoromethane	1.0	4,660	75-69-4
Cfc-12 Dichlorodifluoromethane	1.0	10,200	75-71-8
CFC-113 1,1,2-Trichlorotrifluoroethane	0.viii	6,130	76-13-one
Cfc-114 Dichlorotetrafluoroethane	one.0	8,590	76-14-two
Cfc-115 Monochloropentafluoroethane	0.6	vii,670	76-fifteen-3
Grouping Two
Halon 1211 Bromochlorodifluoromethane	3.0	ane,750	353-59-3
Halon 1301 Bromotrifluoromethane	10.0	6,290	75-63-8
Halon 2402 Dibromotetrafluoroethane	6.0	1,470	124-73-two
Group Iii
Cfc-13 Chlorotrifluoromethane	1.0	13,900	75-72-9
CFC-111 Pentachlorofluoroethane	one.0		354-56-3
Chlorofluorocarbon-112 Tetrachlorodifluoroethane	i.0		76-12-0
CFC-211 Heptachlorofluoropropane	1.0		422-78-6
Cfc-212 Hexachlorodifluoropropane	one.0		3182-26-i
CFC-213 Pentachlorotrifluoropropane	1.0		2354-06-v
CFC-214 Tetrachlorotetrafluoropropane	1.0		29255-31-0
Cfc-215 Trichloropentafluoropropane	1.0		1599-41-3
CFC-216 Dichlorohexafluoropropane	1.0		661-97-two
CFC-217 Chloroheptafluoropropane	i.0		422-86-6
Group IV
CCI4 Carbon tetrachloride	1.1	1,730	56-23-5
Group V
Methyl chloroform one,1,1-trichloroethane	0.i	160	71-55-6
Group Vi
CHthreeBr Methyl bromide	0.vii	2	74-83-9
Group Vii
CHFBr2	one.0
CHFiiBr (HBFC-12B1)	0.74
CH2FBr	0.73
C2HFBrfour	0.3–0.8
CiiHF2Br3	0.v–1.8
C2HF3Brtwo	0.4–ane.vi
C2HF4Br	0.7–1.ii
C2H2FBriii	0.1–1.ane
CtwoHtwoF2Br2	0.ii–one.5
CiiH2F3Br	0.7–1.6
CtwoH3FBr2	0.1–1.7
CtwoH3FiiBr	0.2–1.1
C2H4FBr	0.07–0.1
C3HFBr6	0.three–1.5
C3HFtwoBrfive	0.two–1.nine
C3HFthreeBrfour	0.3–one.eight
C3HF4Br3	0.5–2.2
C3HF5Brii	0.9–2.0
C3HFsixBr	0.seven–3.iii
CthreeH2FBrfive	0.1–1.9
C3HiiF3Briv	0.2–2.1
CiiiHtwoFthreeBrthree	0.2–v.half-dozen
C3H2FivBr2	0.3–7.five
C3H2FfiveBr	0.9–i.iv
CiiiH3FBriv	0.08–ane.ix
C3HiiiFiiBrthree	0.1–iii.one
C3HiiiF3Brii	0.1–2.v
C3H3FfourBr	0.3–4.4
C3HfourFBrthree	0.03–0.iii
CthreeH4F2Br2	0.ane–1.0
C3H4F3Br	0.07–0.8
C3H5FBr2	0.04–0.four
C3HfiveF2Br	0.07–0.8
CiiiH6FBr	0.02–0.7
Grouping VIII
CH2BrCl Chlorobromomethane	0.12
Class Two	0.04	148	75-43-4
HCFC-21 Dichlorofluoromethane	0.055	1,760	75-45-six
HCFC-22 Monochlorodifluoromethane	0.02		593-70-4
HCFC-31 Monochlorofluoromethane	0.01–0.04		354-fourteen-3
HCFC-121 Tetrachlorofluoroethane	0.02–0.08	59	354-21-2
HCFC-122 Trichlorodifluoroethane	0.02	79	306-83-2
HCFC-123 Dichlorotrifluoroethane	0.022	480	2837-89-0
HCFC-124 Monochlorotetrafluoroethane	0.01–0.05		359-28-four
HCFC-131 Trichlorofluoroethane	0.01–0.05		1649-08-7
HCFC-132b Dichlorodifluoroethane	0.02–0.06		75-88-7
HCFC-133a Monochlorotrifluoroethane	0.11		1717-00-half-dozen
HCFC-141b Dichlorofluoroethane	0.065		75-68-3
HCFC-142b Monochlorodifluoroethane	0.01–0.07		422-26-4
HCFC-221 Hexachlorofluoropropane	0.01–0.09		422-49-i
HCFC-222 Pentachlorodifluoropropane
HCFC-223 Tetrachlorotrifluoropropane	0.01–0.08		422-52-6
HCFC-224 Trichlorotetrafluoropropane	0.01–0.09		422-54-8
HCFC-225ca Dichloropentafluoropropane	0.025	127	422-56-0
HCFC-225cb Dichloropentafluoropropane	0.033	525	507-55-1
HCFC-226 Monochlorohexafluoropropane	0.02–0.i	620	431-87-8
HCFC-231 Pentachlorofluoropropane	0.05–0.09		421-94-3
HCFC-232 Tetrachlorodifluoropropane	0.008–0.1		460-89-9
HCFC-233 Trichlorotrifluoropropane	0.007–0.2		7125-84-0
HCFC-234 Dichlorotetrafluoropropane	0.01–0.28		425-94-5
HCFC-235 Monochloropentafluoropropane	0.03–0.52		460-92-4
HCFC-241 Tetrachlorofluoropropane	0.004–0.09		666-27-3
HCFC-242 Trichlorodifluoropropane	0.005–0.13		460-63-9
HCFC-243 Dichlorotrifluoropropane	0.007–0.12		460-69-5
HCFC-244 Monochlorotetrafluoropropane	0.009–0.14
HCFC-251 Trichlorofluoropropane	0.001–0.01		421-41-0
HCFC-252 Dichlorodifluoropropane	0.005–0.04		819-00-1
HCFC-253 Monochlorotrifluoropropane	0.003–0.03		460-35-5
HCFC-261 Dichlorofluoropropane	0.002–0.02		420-97-3
HCFC-262 Monochlorodifluoropropane	0.002–0.02		421-02-03
HCFC-271 Monochlorofluoropropane	0.001–0.03		430-55-vii

Notes: Class I ODS listed in Groups 1–5 are identified in Title VI of the Clean Air Act.

Course I ODS listed in Groups half-dozen and vii, methyl bromide and hydrobromofluorocarbons, are identified in EPA׳s Accelerated Phaseout final dominion.

Form I ODS listed in Group viii, chlorobromomethane, is identified in EPA׳south Chlorobromomethane Phaseout terminal rule.

Abbreviations: CAS, chemical abstracts service; EPA, environmental protection bureau; GWP, global warming potentials; ODPs, ozone depletion potentials; ODSs, ozone depletion substances.

Source: US Environmental Protection Agency. Reproduced from Environmental Protection Agency (EPA). Substitute refrigerants under SNAP equally of October 21, 2014. Available from: https://world wide web.epa.gov/ozone/snap; 2014 [accessed 12.03.xvi].

As an example, a compound with an ODP of 0.2 was, roughly, about 1-fifth as harmful equally R-11. The ODP of any refrigerant (i.e., R-X) was defined as the ratio of the total amount of ozone destroyed by a fixed amount of R-10 to the amount of ozone destroyed by the same mass of R-eleven, as follows:

$\text{ODP}(\text{R}‐\text{10})=(\text{ozone}\mathrm{loss}\mathrm{because}\mathrm{of}\text{R}‐\text{X})/(\text{ozone}\mathrm{loss}\mathrm{considering}\mathrm{of}\text{R}‐11)$

CFCs were considered fully halogenated. This means that there were no hydrogen atoms, but halogens (chlorine, fluorine, bromine, etc.). Equally mentioned earlier, the refrigerants with hydrogen atoms were known as "HCFCs" (east.yard., R-22, R-123, R-124, R-141b, and R-142b); they were not fully halogenated and were less stable than CFCs. The computed ODP values for HCFC refrigerants were very low (on the order of 0.01 to 0.08) compared to the values estimated for CFCs (on the society of 0.7 to one, for R-11, R-12, R-113, and R-114 and about 0.four for R-115). It is for this reason that the Montreal Protocol had a principal goal of phasing out these types of Cfc refrigerants. There is a family of refrigerants with an estimated ODP value of zippo and without any chlorine, called "HFCs." Some examples of HFCs mentioned above are R-125, R-134a, R-143a, and R-152a. Inquiry and evolution activities accept particularly focused on the use of these ozone- and surroundings-friendly refrigerants.

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Central PRINCIPLES GOVERNING SOLVENTS Employ

ESTANISLAO SILLA , ... GEORGE WYPYCH , in Handbook of Solvents (2nd Edition), Volume 1, 2014

2.3.17 OZONE – DEPLETION AND Creation POTENTIAL

Ozone depletion potential is measured relative to CFC-11 and it represents the amount of ozone destroyed by emission of a vapor over its unabridged atmospheric lifetime relative to that caused by the emission of the same mass of Cfc-11.

Urban ozone formation potential is expressed relative to ethene. Information technology represents the potential of an organic solvents vapor to form ozone relative to that of ethene ((g O_iii/g solvent)/(g O₃/grand ethene)). Several groups of solvents, including alcohols, aldehydes, amines, aliphatic and effluvious hydrocarbons, esters, ethers, and ketones are active in ozone formation. Aldehydes, xylenes, some unsaturated compounds, and some terpenes are the most active among those.

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13th International Symposium on Process Systems Engineering science (PSE 2018)

Resul Al , ... Gürkan Sin , in Computer Aided Chemical Technology, 2018

3.ane Information collection

The experimental property data for GWP and ODP (100 years timeline for both) were collected from a recent paper from Huijbregts et al., and the information for LC50 were collected from the Ecotoxicology Database (ECOTOX) of U.S. Ecology Protection Agency. Available data for GWP covers chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, chlorocarbons and hydrochlorocarbons, halons, fully fluorinated species, halogenated alcohols and ethers, whereas for ODP available data is much more limited, to those of chlorofluorocarbons, hydrochlorofluorocarbons, and halons. Earlier proceeding with model evolution, an outlier treatment function is applied to the data, which trims the observations that are more than 1.5 interquartile ranges to a higher place the upper quartile or below the lower quartile. This ensures the developed model are robust to the outliers in the data. To make up one's mind the predictors for the multiple linear regression model, an occurrence matrix of each specific group present in the each different compound is generated using ICAS© software, which requires canonical SMILES expression of compounds. A robust regression using a nonlinear to the lowest degree squares solution algorithm (trust region reflective algorithm of MATLAB'due south lsqnonlin solver) is performed to calculate grouping contribution factors. The following functions are applied to the investigated properties.

(2) $f\left(\mathit{GWP}\right)=log\left(\mathit{GWP}\right)={\sum }_i{N}_i{C}_i$

(3) $f\left(\mathit{ODP}\right)=log\left(\mathit{ODP}\right)={\sum }_i{\mathrm{Northward}}_i{C}_i$

(4) $f\left({\mathit{LC}}_{50}\right)=-log\left({\mathit{LC}}_{50}\right)+{\mathit{LC}}_{50}={\sum }_i{\mathrm{Due\; north}}_i{C}_i\mathit{with}{\mathit{LC}}_{{50}_0}=2.97$

Using the occurrence matrix and contribution factors as described in in a higher place equations, the starting time social club GC predictions are obtained. An assessment on the goodness of fit of different models is made using the R2 metric, which tin be interpreted every bit the proportion of variability in property data that can exist accounted for by the set of predictors in the model. A skillful estimate of the generalization potential of the adult models tin be obtained using cross-validation. To account for that, one fifth of the data was held out equally a exam sample, and the model was trained on the remaining data. Performance measures, such as root mean squared error (RMSE) and mean absolute error (MAE), are calculated for the test set as shown in Eq. (five) and (half dozen) respectively.

(5) $\mathit{RMSE}=\sqrt{\frac{1}{N}{\sum }_{i=1}^N{\left({\mathrm{y}}_i^{\mathit{exp}}-{\mathrm{y}}_i^{\mathit{pred}}\right)}^{\mathrm{two}}}$

(6) $\mathit{MAE}=\frac{1}{N}{\sum }_j^N\left|{\mathrm{y}}_i^{\mathit{exp}}-{\mathrm{y}}_i^{\mathit{pred}}\right|$

When developing predictive models on datasets with strong clusterization, it is crucial to select a training gear up that is representative of the overall data trends. This problem can exist addressed with the use of stratified sampling approach, which takes into business relationship the clusters in the data and generates training and test samples preserving percent of clusters for each set. This was the case with GWP data, and therefore a representative preparation set was created using this arroyo.

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Overview of environmental footprints

Lidija Čuček , ... Zdravko Kravanja , in Assessing and Measuring Environmental Impact and Sustainability, 2015

Indicators of potential ecology impacts

Indicators of potential environmental impacts deal with the potential furnishings and impacts on humans, environmental health, and resources from the LCI (Saur, 1997). They are divided into midpoint-oriented and end-point-oriented or harm touch on categories (Effigy 5.5).

Figure v.v. From LCI to endpoint harm categories.

The post-obit midpoint categories are unremarkably considered:

•

Ozone depletion potential is the potential for the reduction in the protective stratospheric ozone layer. The ozone-depleting substances are freons, chlorofluorocarbons, carbon tetrachloride, and methyl chloroform. It is expressed as Chlorofluorocarbon-eleven equivalents.

•

Global warming potential represents the potential modify in climate owing to increased concentrations of CO₂, CH_iv, and other GHG emissions that trap estrus. Information technology leads to increased droughts, floods, losses of polar ice caps, sea-level rising, soil wet losses, forest losses, changes in wind and bounding main patterns, and changes in agricultural production. It is expressed in CO₂ equivalents usually for time horizon 100   y.

•

Acidification potential is based on the potential of acidifying pollutants (And then₂, NO ₁₀ , HCl, NH₃, HF) to form H⁺ ions. Information technology leads to damage to plants, animals, and structures. It is expressed in SO₂ equivalents.

•

Eutrophication potential leads to an increase in aquatic plant growth attributable of nutrients left by over-fertilization of water and soil, such every bit nitrogen and phosphorus. Nutrient enrichment may cause fish death, declining h2o quality, decreased biodiversity, and foul odors and tastes. It is expressed in ${\mathrm{PO}}_4^{3-}$ equivalents.

•

Photochemical ozone creation potential is too known equally ground-level smog, photochemical smog, or summer smog. Information technology is formed inside the troposphere from a variety of chemicals including NO _x , CO, CH₄, and other volatile organic compounds (VOCs) in the presence of high temperatures and sunlight. It has negative impacts on human health and the environment and is expressed as C₂H₄ equivalents.

•

Ecotoxicity (freshwater, marine, terrestrial) potential focuses on the emissions of toxic substances into the air, water, and soil. It includes the fates, exposures, and effects of toxic substances and is expressed every bit ii,4-dichlorophenoxyacetic acid equivalents.

•

Man toxicity potential deals with the effects of toxic substances on human wellness. It enables relative comparisons betwixt a larger number of chemicals that may contribute to cancer or other negative human furnishings for the infinite time horizon. It is expressed as 1,iv-dichlorobenzene equivalents.

•

Abiotic depletion potential is concerned with the protection of homo welfare, human health, and ecosystems, and represents the depletion of not-renewable resources (abiotic, non-living (fossil fuels, metals, minerals)). It is based on concentration reserves and the rate of de-accumulation and is expressed in kg antimony equivalents.

•

Land use

•

Water utilise

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Refrigeration and Estrus-Pump Systems

Ronald W. James , Terry C. Welch , in Ac System Design, 2017

Refrigerants

The platonic refrigerant would be nontoxic and nonflammable and should take

•

cypher ozone depletion potential (ODP),

•

zip global warming potential (GWP),

•

short atmospheric lifetime.

These factors accept become i of the main driving forces in option of a refrigerant fluid, which should as well have

•

a large refrigeration effect requiring a small mass flow rate,

•

a pocket-sized amount of piece of work to be done during compression,

•

a small vapour specific volume.

These characteristics would upshot in a smaller compressor and a lower power requirement. Additionally, for reliable plant operation,

•

the temperature of the discharge superheated vapour from the compressor should be depression (generally 130°C is a maximum), to avoid oil breakdown;

•

the evaporating pressure should be above atmospheric, and the condensing pressure level should be below the disquisitional pressure of the refrigerant.

All chlorofluorocarbon and hydrochlorofluorocarbon refrigerants are at present banned for apply in refrigeration equipment. The about environmentally friendly refrigerant fluids in terms of ODP and GWP are ammonia, propane, and blends of propane/butane. Notwithstanding, all these fluids have toxicity and flammability problems. Ammonia is used in air conditioning applications but requires a divide plant room and produces chilled water for cooling purposes. Propane is used in small-chapters air conditioning plants and has to meet current wellness and safety and flammability requirements.

In that location is currently enquiry and evolution work with carbon dioxide as a refrigerant, and at that place are applications where it is used.

A group of fluids currently being developed are hydrofluoroolefins. They are propane-based fluids, unsaturated hydrofluorocarbons with refrigerant numbers HFC1234yf and HFC1234ze; they are being introduced to replace R134a. Propane is now used in centrifugal compressors and vehicle ac. A summary of refrigerants is given in Table ix.2.

Table 9.2. Refrigerants

Refrigerant	Type	ODP	GWP	Atmospheric lifetime (years)
R12	Chlorofluorocarbon	0.ix	8500	102
R22	HCFC	0.06	1700	13.3
R134a	HFC	0	1300	fourteen
R407C	HFC blend	0	1610	36
R410A	HFC blend	0	1900	36
Ammonia (R717)	Natural compound	0	0	<   1
Propane (R290)	HC	0	iii	<   1
R1234yf	HFC unsat.	0	half dozen	Very low
R1234ze	HFC unsat.	0	6	Very low

CFC, chlorofluorocarbon; HCFC, hydrochlorofluorocarbon; HFC, hydrofluorocarbon; HFC, alloy consists of more than one HFC; HC, hydrocarbon; ODP, zippo ozone depletion potential; GWP, zero global warming potential; TEV, thermostatic expansion valve.

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Steam turbines for solar thermal and other renewable energies

N. Okita , ... M. Nishimura , in Advances in Steam Turbines for Modern Power Plants, 2017

20.iv.3 Spiral type ORC turbine

Working fluid often practical in this blazon of turbine is HFC-245fa, because its ozone depletion potential is zero and it results in a very small amount of environmental pollution.

i.

Components of the ORC system (refer to Fig. twenty.9)

Evaporator

The evaporator makes working fluid liquid evaporate by the heat of the steam or hot water. The plate estrus exchanger with loftier efficiency is adopted.

Semi-hermetic screw turbine arrangement

The ORC system generates electricity by rotating a screw turbine (= a generator rotor) with the evaporated working fluid. A screw rotates in response to the catamenia rate of fluid.

Condenser

The rut exchanger (condenser) makes working fluid gas condense past cooling water. The plate blazon oestrus exchanger of high efficiency is adopted for the condenser, the same as the evaporator.

Fluid pump

The fluid pump is a semi-hermetic centrifugal pump without a seal, and it pressurizes working fluid into the evaporator. The pump is controlled automatically in order to keep the best generating electric operation.

Figure twenty.ix. Organic Rankine cycle organisation of screw turbine.

ii.

Screw turbine and generator system

The system adopts an efficient interior permanent magnet (IPM) generator which uses reluctance through magnetic resistance in addition to magnetic torque by imbedding a permanent magnet in the rotor itself.

An IPM generator has a college efficiency than an consecration generator, therefore an IPM generator is smaller than an consecration generator.

The screw turbine shaft and the generator rotor shaft are combined along the same axis, and the screw turbine is semi-hermitic. Thus, this spiral turbine has a unproblematic structure without shaft-seals, a coupling, nor a bearing on the generator side.

Long and stable performance is enabled by this uncomplicated system without leakage of working fluid and lubricant.

This system has been adult based on the technology of a semi-hermetic oil-flooded spiral refrigeration organisation. The screw turbine is likewise reliable without system fluctuation, because of strong rigidity of the rotating rotor. And this system has high efficiency for all operation ranges, maintaining the same level at part load.

A schematic diagram of the expansion process of the screw turbine is shown in Fig. 20.10. The pressure in the expansion process of the spiral turbine is varied in the operated position which is formed past the male person rotor, the female person rotor, and the casing. The pressure difference between the low-pressure level areas and loftier-pressure level areas rotates the rotors. The high-pressure working fluid gas is introduced from the charging side, and the expansion of working fluid gas makes the rotor spin. The rotor is rotated past repeated gas expansion in the spiral turbine, and the rotor rotation generates electricity continuously.

Effigy 20.10. Expansion stroke of screw expander.

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Plastics Solutions for Practical Problems

Michel Biron , in Thermoplastics and Thermoplastic Composites (Third Edition), 2018

vii.27.three.2 Pollution

Among numerous ecology parameters, three indicators are considered

•

GWP: global warming potential in (kgCO₂ eq)

•

ODP: Ozone depletion potential in (gCFC ₁₁ eq)

•

Aeq: acidification potential in (gSO₂ eq).

Table vii.91 displays rounded results for the main phases:

Table 7.91. Fuel Tanks: Environmental Indicators

		Manufacturing		Apply		Stop of Life	Total
		Inputs	Manufacturing	Inputs	Use Stage	Subtotal
Metallic	GWP (kgCO2 eq)	216	4	26	427	−23	650
Plastic	GWP (kgCO2 eq)	54	four	17	274	−iii	346
Metal	ODP (gCFC11 eq)	0.03	0	0.002	0	−0.001	0.031
Plastic	ODP (gCFC11 eq)	0.05	0	0.001	0	0	0.051
Metal	Aeq (gSO2 eq)	404	3	28	529	−44	920
Plastic	Aeq (gSO2 eq)	96	3	18	339	−5	451

GWP, global warming potential; ODP, Ozone depletion potential; Aeq, acidification potential.

For steel tanks (ancillary subparts may include metals and plastics):

•

Manufacturing:

•

Inputs include steel sheet, dies and tools, etc.

•

Manufacturing steps include forming, welding, consumed energy, etc.

•

Use stage:

•

Mainly fuel consumption.

•

Recycling:

•

Dismantling

•

Steel making from metal scraps; recycling or landfilling of plastics parts.

For plastics tanks:

•

Manufacturing:

•

Inputs include resin, dies, molds and tools, etc.

•

Manufacturing steps include extrusion blow molding, welding, consumed energy, etc.

•

Use phase:

•

Mainly fuel consumption.

•

Recycling:

•

Dismantling

•

Recycling or landfilling of plastics part, recycling of metal parts.

Other different data can be constitute elsewhere because the results depend on the used assumptions.

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Principles and operation of refrigeration and rut pump systems

Andriy Redko , ... Ronald DiPippo , in Depression-Temperature Energy Systems with Applications of Renewable Energy, 2020

1.half-dozen.two Evolution of refrigerants

The world'southward refrigeration and comfort-control industries depend entirely on the decisions of the global community regarding cooling agents. Several generations of refrigerants have already changed over the past few decades. Some substances, which until recently were considered the most upwards-to-appointment and environmentally condom, take now been withdrawn from use. Below we trace the evolution of working fluids for refrigeration machines.

Starting time generation – Everything and annihilation that worked. Conventional solvents and other volatile liquids were the most commonly used cooling agents for the first hundred years. In fact, the first generation of cooling agents included everything that worked and was available. Almost all the commencement cooling agents were combustible and toxic, and some were fifty-fifty chemically active. Accidents ordinarily occurred during the functioning of refrigeration equipment. Some companies vigorously pushed propane (R290) as a "prophylactic, odorless cooling agent" over ammonia (R717). Accidents, peculiarly in domestic situations, often provoked changes in design and new regulations.

Second generation: Safety and durability. The 2d generation was marked by the transition to fluorine compounds to increase the safety and shelf life of refrigeration systems. Prior to this, early on attempts to supplant "water ice boxes" with refrigerators, in which either methyl formate (R611) or sulfur dioxide (R764) were used as a cooling agent, were unsuccessful; it was impossible to eliminate leakage of these toxic substances. Under the slogan "The refrigeration manufacture needs a new cooling agent, if it hopes to use it everywhere," a cooling agent R12 was developed by General Motors under the direction of Charles Kettering. Industrial production of R12 began in 1931, and of R11 in 1932. Chlorofluorocarbons (CFCs) and afterward hydrochlorofluorocarbons (HCFCs) dominated in the second generation of cooling agents, particularly since the 1950s, in domestic and industrial air conditioners and rut pumps. Ammonia has been and remains the most popular cooling agent in large industrial systems, peculiarly in the field of production and preservation of products and beverages, and in large water ice-houses serving fishing fleets.

3rd generation: Protection of the ozone layer (1997). Hypotheses regarding the destruction of the ozone layer and the causes of the formation of "ozone holes" were adult; e.k., the processes of cosmic radiation and the periodic growth of solar activity, the processes of irresolute atmospheric circulation, etc. According to the hypothesis of the influence of ultraviolet radiation, the breaking of chlorine and bromine bonds of cooling agents makes them highly receptive to absorbing oxygen. Besides the ozone problem, the emission of sure cooling agents has an impact on the "greenhouse effect."

The Montreal Protocol (1987) identified refrigerants that were destroying the ozone layer and those with the potential of destroying it. The Ozone Depletion Potential (ODP) was defined in order to classify refrigerants. Every bit they were the worst ones, R11 and R12 are assigned a value of unity, i.due east., ODP-R11≡1 and ODP-R12≡i. At present, at that place are the post-obit synthetic refrigerants containing ozone-depleting substances:

one.

Refrigerants of the Chlorofluorocarbon course. CFC molecules contain chlorine, fluorine and carbon atoms; they are greenhouse gases and ozone depleting with ODP   >   0.1;

two.

Refrigerants of the HCFC grade. They are also greenhouse gases and ozone-depleting gases with lower ODP of 0   <   ODP   <   0.1.

Fourth generation: Counteraction to global warming. The Kyoto Protocol (1997) and "The Paris Summit on Climate" (2015) defined the possibilities of protecting the surround from greenhouse gas emissions. The Kyoto Protocol identified substances that impact the Earth's climate. Greenhouse gases include carbon dioxide, methane, nitrous oxide, sulfur hexafluoride and all constructed refrigerants. The Global Warming Potential (GWP) was introduced. Carbon dioxide potential is taken as unity, i.e., GWP-CO₂ ≡ 1.

The GWP compares the amount of heat that affects global warming that is absorbed by a certain mass of refrigerant (ordinarily ane   kg) with the amount of rut absorbed by the same mass of CO_two. During the transition menstruation, ozone-friendly refrigerants (i.east., ODP   =   0) were created. There be the following synthetic ozone-prophylactic cooling agents with a high GWP:

•

HFC refrigerants containing fluorine, hydrogen and carbon atoms with ODP   =   0.

•

Refrigerants of the PFC class (perfluorocarbons), that are greenhouse- and ozone-friendly gases containing fluorine and carbon atoms with ODP   =   0.

Current generation (afterward 2010). Since 2010, ozone-depleting refrigerants R21, R22, R123 and R1245b are not allowed. Until 2025 in Europe, the use of refrigerants with GWP   <   2500 is permitted; after 2030 it is planned to not use refrigerants with GWP   >   150. Refrigerants R134a, R125, R404a, R407c, R507a, R410a, and in the future R32 volition not be immune. The time is coming for hydrofluoroolefins (HFOs), eastward.m., R1336mzz, R123yf, R1234ze, and R1233zd – all having GWP   <   ten. Mixtures of refrigerants based on HFO, namely, R448a, R449a, R450a, R513a, and others are being manufactured.

In developed countries, chlorofluorobromohydrocarbons (CFBHC) are no longer used in cooling and air conditioning systems. HFC mixtures, namely, R407c and R410a are considered an acceptable replacement for the ozone-depleting refrigerant R22. ASHRAE 34-2007 allows the utilize of ozone-safe refrigerants ranging from R429a to R437a, and R510a. The following sources of information may be used for the designation of refrigerants and their possible replacements as environmental restrictions reduce the available working fluids [21–25].

Projecting into the future, information technology seems clear that the employ of synthetic refrigerants will become more than and more restricted. Table 1.4 shows the electric current situation based on the Montreal Protocol and the EU F-Gas 2 Impact. Tabular array 1.5 shows the bans and restrictions facing the refrigerants. All HCFCs are subject field to phase-down in the time to come owing to their medium-level ODP. From Table i.4, it can be seen there are but seven natural refrigerants and ii HFOs that are completely free of restrictions at this time.

Tabular array one.4. Classification of selected refrigerants for ODP and GWP [26].

Type	R-number	ODP a	ODP level	GWP b	GWP level
Natural	717	0	Zero	0	Zip
Natural	744	0	Zero	i	Low
Natural	1270	0	Naught	2	Depression
Natural	290	0	Null	3	Low
Natural	600a	0	Cypher	3	Depression
Natural	1150	0	Zero	4	Depression
HFO	1234yf	0	Naught	iv	Low
HFO	1234ze	0	Zero	six	Low
Natural	170	0	Zero	6	Depression
HFC	32	0	Nil	675	Medium
HFC	134a	0	Cypher	1430	Medium
HFC	407C	0	Aught	1774	Medium
HFC	437A	0	Goose egg	1805	Medium
HFC	407F	0	Zip	1825	Medium
HFC	442A	0	Zero	1888	Medium
HFC	410A	0	Zero	2088	Medium
HFC	407A	0	Zippo	2107	Medium
HFC	427A	0	Nix	2138	Medium
HFC	438A	0	Zero	2265	Medium
HFC	423A	0	Zero	2280	Medium
HFC	417A	0	Zero	2346	Medium
HFC	424A	0	Goose egg	2440	Medium
HFC	422D	0	Zero	2729	High
HFC	422A	0	Nada	3143	High
HFC	434A	0	Zero	3245	High
HFC	428A	0	Zippo	3607	High
HFC	MO89	0	Zero	3805	Loftier
HFC	404A	0	Nada	3922	High
HFC	507A	0	Nada	3985	High
HFC	508B	0	Zero	13396	Loftier
HFC	23	0	Zip	14800	High
HCFC	123	0.060	Medium	77	Low
HCFC	402B	0.030	Medium	2416	Medium
HCFC	401A	0.033	Medium	1182	Medium
HCFC	401B	0.036	Medium	1288	Medium
HCFC	409A	0.046	Medium	1909	Medium
HCFC	22	0.055	Medium	1810	Medium
HCFC	402A	0.019	Medium	2788	Loftier
HCFC	408A	0.024	Medium	3152	High
CFC	502	0.33	High	4657	High
CFC	11	ane	Loftier	4750	High
CFC	12	1	High	10900	Loftier

a

Ozone Depletion Potential, UNEP (2006): R11   =   R12   ≡   1.

b

Global Warming Potential (100 year), IPCC fourth Cess Report, 2007: CO₂  ≡   one.

Table one.5. Restrictions and bans on refrigerants in Tabular array 1.iv [26].

ODP level	Montreal protocol	GWP level	Level	European union F-Gas ii impact
Zero	No restrictions	<150	Low	No controls
Medium	Subject to consumption phase down	150–2500	Medium	Some supply restrictions and new equipment utilize bans
High	100% global production & consumption ban	>2500	Loftier	Substantial supply and utilise restrictions and new equipment bans

The very first synthetic refrigerants developed in the 1930s and deployed thereafter were the all-time ever conceived from a strictly technical performance standpoint. They were crafted to yield excellent efficiency with outstanding rubber characteristics for personnel who had to work with them. The story is told by Charles Kettering [27] about how Thomas Midgley, the engineer who led the evolution team at Frigidaire, introduced R12 to an audience by inhaling the vapor from a beaker, filling his lungs with R12, and so gently releasing information technology over a called-for candle. It extinguished the flame and he was not harmed by the vapor, thereby demonstrating both non-toxicity and non-flammability simultaneously. Information technology was only decades later on that the detrimental impact CFCs on the surround came to calorie-free.

Each new refrigerant created in the laboratory has both benefits, mainly environmental, and drawbacks, mainly technological. Certainly they are less effective from an efficiency standpoint, requiring more than energy input to operate the RMs for the same cooling effect. Actual operation of RMs and HPs has identified the technical bug related to synthetic working substances. Ozone-safe refrigerants of the HFC and PFC classes are very expensive compared to, say, R22. Higher pressure level for the system processes requires an increase in the strength of the estrus exchanger materials and metal consumption; the necessity to use expensive high-hygroscopic, polyester, synthetic oils for lubrication; and in the case of refrigerant mixtures, the requirement to completely replace the refrigerant in the RM when there is whatever leakage, no matter how small, since the preferential leakage of the low-boiling component significantly alters the thermal properties of the working fluid and hence the system performance.

It might be possible that only natural refrigerants will be allowed some time in the about future, essentially returning the world to the starting point of refrigeration; see Fig. 1.18.

Fig. i.18. Trends in working fluids for refrigeration units: a closed wheel.

Redrawn from [28].

Decisions by international commissions will control what engineers may employ as working fluids in refrigeration machines and estrus pumps. Beginning proposed by Passet in 1979 [29], several studies accept been adult on the ground of the integrated concept of sustained development involving ecological, social and economic considerations; see Fig. one.nineteen. Only where the 3 aspects are simultaneously satisfied can a solution be considered sustainable and therefore acceptable.

Fig. 1.nineteen. Triune concept of sustained evolution [30].

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Oxide-based Systems at the Crossroads of Chemistry

V. Dal Santo , ... L. Sordelli , in Studies in Surface Science and Catalysis, 2001

1 INTRODUCTION

Carbon tetrachloride finds unlike industrial uses equally solvent, as dopant in semiconductor industries, as raw cloth [one–iii].

All the same, together with other chlorinated compounds like PCBs and CFCs, it possesses noxious furnishings on environment, specially a high ozone potential depletion. Information technology was, in fact, classified in the IV grouping among CFCs and so its utilize was banned, in adult countries, from 1996.

Among the more diffuse CFCs disposal methods, similar thermal combustion [4,v], catalytic combustion [six], catalytic hydrogenation is i of the more than promising, owning to the low reaction temperature and the product of useful compounds, without pollutants by-products like dioxins, CO, Cl₂ and COCl_two.

It has been reported that catalysts obtained from H₂PtCl₆ on MgO [vii,8] showed skilful conversion and selectivities for the hydrodechlorination of CCl_iv to CHCl_iii, beingness less prone to deactivation than Pt/Al_iiO₃ at lower H₂/CCl₄ ratio. This behavior was ascribed to the basicity of MgO that retards the coking.

On the other paw, Pd catalysts were used, with good results, for the fractional dehalogenation of chloro-fluorocarbons to hydrofluorocarbons [ix–11], and of chlorobenzenes [12], but at present there are few studies on chlorinated aliphatic substrates like CCl_four.

The aim of this work is to test different Pt and Pd catalysts supported on basic MgO in the hydrodechlorination of CCl_iv. Particular attending was devoted to the pick of the organometallic precursor, in order to maintain the basic backdrop of activated MgO and consequently to increment metal support interactions. A specific metal-back up interaction on Pd(acac)₂/MgO⁵⁰⁰ catalysts was observed by previous studies [xiii].

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